Washington State Route 125

State Route 125
A map of the Walla Walla area with SR 125 highlighted in red
Route information
Auxiliary route of US 12
Maintained by WSDOT
Length	23.65 mi[1] (38.06 km)
Existed	1964–present
Major junctions
South end	OR 11 near College Place
North end	SR 124 near Prescott
Location
Country	United States
State	Washington
Counties	Walla Walla
Highway system
State highways in Washington Interstate US State Scenic Pre-1964 1964 renumbering Former
← SR 124 → SR 127

State Route 125 (SR 125) is a state highway in Walla Walla County, Washington, United States. It travels 24 miles (39 km) south from the city of Walla Walla to the Oregon state border and north to a junction with SR 124 near Prescott. The highway continues south towards Pendleton, Oregon, as OR 11. SR 125 also has a spur route in Walla Walla that connects it to an interchange with U.S. Route 12 (US 12).

SR 125 follows a historic wagon road, the Mullan Road, and several railroads that were built in the late 19th century. The road from the Oregon border to Walla Walla was added to the state highway system in 1923 as a branch of State Road 3 (later US 410), while the remainder of the highway from Walla Walla to Prescott was designated as part of Secondary State Highway 3E in 1937. The two highways were combined to form SR 125 during the 1964 state highway renumbering.

The Oregon–Walla Walla highway was originally a two-lane road that was the site of hundreds of collisions in the 1960s, prompting the state government to consider new designs. After proposals to build a bypass to carry SR 125 around Walla Walla were shelved, the state began construction of a four-lane divided highway in 1987. It was completed the following year and improved with traffic signals in the late 1990s.